SHIC Wean-to-Harvest Biosecurity: Risk and Protective Factors for PRRSV Outbreaks

Jan 12, 2026

As an outcome of the Swine Health Information Center Wean-to-Harvest Biosecurity Research Program, in partnership with the Foundation for Food & Agriculture Research and Pork Checkoff, a newly published paper in Veterinary Sciences outlines risk and protective factors for PRRSV outbreaks identified through an industry-wide biosecurity survey.  Utilizing a questionnaire to gather data, the survey project completed in April 2025 reported biosecurity practices across 3,680 sites. In a second study, 95 wean-to-harvest sites were followed with monthly oral fluid testing for PRRSV. Researchers characterized which practices increased or decreased the likelihood of a PRRS outbreak. Risk factors included transporting pigs of unknown PRRSV status, rendering mortalities, and employees working across multiple sites living together. Protective factors included assigned vehicle parking, farm-owned equipment, and overnight downtime for caretakers working across multiple sites. 

Find the full paper in Veterinary Sciences here and the industry summary for project #23-029 on this page. Read more about the Wean-to-Harvest Biosecurity Research Program here. 

Led by Drs. Mariah Musskopf and Gustavo Silva at Iowa State University, this study assessed current bioexclusion practices among a diverse group of producers across swine-producing states in the US. In addition, the study developed methods that veterinarians, production managers, and producers could implement to improve on-farm biosecurity including the development of a risk assessment tool. Overall, findings showed that biosecurity on wean-to-harvest sites is inconsistent across the industry and that tools for increasing biosecurity could include relatively simple practices such as bench entry. 

To assist with the management of increased PRRS activity detected during winter months, SHIC is highlighting the project information regarding risk and protective factors from PRRSV outbreak data to help producers, veterinarians, and other stakeholders apply key learnings from the project. In the forest plot graph (Figure 1), odds ratios for various biosecurity and management practices associated with PRRSV outbreaks are displayed. Practices with odds ratios above 1 indicate increased odds of outbreak (red dots), while those below 1 suggest protective effects (green dots).

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Video: Season 7, Episode 1: Managing Risk and Seeing Opportunities in U.S. Pork Production

Today’s episode features three guests discussing the similarities and differences between pork production in the United States and Brazil, along with strategies for managing risk in today’s industry while recognizing and acting on opportunities. First, Dr. Anne Caroline de Lara, executive manager of live pig production at Seara Alimentos, a JBS company in Brazil, is joined by Dr. Matthew Turner, head of operations for JBS Live Pork. Together, they discuss how labor, climate and ventilation challenges vary between Brazil and the United States, while underscoring their shared commitment to raising healthy pigs. They also point to lessons producers in both countries can take from one another’s systems and on-farm experiences. Then, Brady Reicks, risk manager at Reicks View Farms, shares his perspective on risk management, drawing from his background in markets and his transition into farming. He discusses how protecting margins varies by operation and offers practical approaches producers can use to make marketing and business decisions with greater confidence rather than hesitation.

Both conversations were recorded at recent industry events focused on swine livability, including the International Conference on Pig Livability and Iowa Swine Day.